Essa recently sold his 60% stake in Trillian Capital to the firm's CEO, Eric Wood.

Last month Eskom admitted that it had lied in its defence of payments totalling R1.6-billion which it made to Trillian and McKinsey.

Corruption Watch director David Lewis - speaking at the Anti-Intimidation and Ethical Practices Forum in Johannesburg on Monday- said his organisation was finalising submissions to the US authorities that would be handed over before the end of the month.

The forum was created to assist people who are being intimidated for exposing workplace corruption.

Lewis said Corruption Watch's submissions would include Public Protector Thuli Madonsela's State of Capture report and a report by advocate Geoff Budlender on his investigations.

Budlender was hired by former Trillian Capital Holdings chairman Tokyo Sexwale to investigate, among other things, allegations that Wood had prior knowledge of the firing by President Jacob Zuma of Finance Minister Nhlanhla Nene.

Nene's firing resulted in the economy losing billions of rands in investments.

Budlender found that Trillian had received payments of more than R250-million from Eskom for work it had not done. He said Trillian's management had obstructed his investigation.